Muscle tears are degenerative type bodily injuries, whose occurrence increase with old age, in particular beyond 70 to 80 years of age. Shoulder muscle tear injuries occur typically when a person repetitively lifts heavy loads above his/her head, and will appear regularly in activities such as swimming, window cleaning, freight handling, strength conditioning exercising, and the like.
It often happens that an important part of the medical treatment of a repaired shoulder muscle requires the stabilization and support of the arm in abduction (away from the patient's sagittal plane) during the rehabilitation healing period which typically lasts between four to twelve weeks, and in general about six weeks. Shoulder muscular injuries can be of different types involving different set of muscles. Different medical treatments involving surgery may be required depending on the injury type and severity. In each case, proper healing requires that the patient's arm be stabilized at a specific angle relative to the body to maintain the shoulder in the ideal position. As the healing progresses, the arm stabilization angle is often reduced, bringing the arm in adduction (closer to the patient's sagittal plane) i.e. gradually closer to its natural position along the body. Furthermore, these injuries typically affect only part of the muscles of the shoulder, often being the supraspinatus (with possibly the infraspinatus) muscle with muscle tear length varying usually between 1 and 20 mm.
After an initial healing period, treatments exercising of the uninjured healthy muscles of the shoulder including the pectoralis major muscle, and possibly the latissimus dorsi muscle—are recommended to maintain tonus of these healthy muscles. This exercising is limited to a certain set of movements that minimize the use of the injured or repaired muscles. For example, in many types of injuries to the rotator cuff, it is recommended after a certain healing period for the patient to repeatedly exercise his/her adduction muscles.
Many of the shoulder orthosis and arm stabilization apparatuses known in the art are used to stabilize the arm in a single static given position. Others offer adjustment mechanisms enabling to change the height at which the arm is stabilized. But these height adjustment mechanisms often require external intervention and cannot be operated unaided by the patient alone. Some also require complex or lengthy procedures, requiring the orthosis to be firstly removed, or involving spare parts and even special tools. Some also comprise unstable harnesses and splint, or they comprise multiple support structures which are often cumbersome and uncomfortable. Furthermore, most of these orthosis do not enable any kind of free arm movement by the patient's arm, which is a major inconvenience when several weeks of rehabilitation are required.
Furthermore orthosis known in the art do not allow for the concurrent flexion/extension of the forearm around the injured arm elbow.